Of course, with smartphones have come a flood of apps, software programs that dramatically extend their capabilities. The Pew Internet and American Life Project has studied this phenomenon, which it has dubbed “Apps Culture”, and has come up with some interesting findings.

Among them:

? 82 percent of U.S. adults use cell phones; 23 percent live in households where there’s no landline. In addition, 59 percent of adults use their phones or a notebook computer to access the Internet

? 43 percent of cell users have apps on their phones, or about 35 percent of the overall adult population. But only 68 percent actually use the apps they have. As you’d expect, the younger, more educated and more affluent a cell user is, the more apt he or she is to have and use mobile apps.

? More common smartphone uses outrank apps for most users. The No. 1 non-voice-call use for phones: taking pictures.

? Free apps rule: Only 13 percent of cell users have actually paid for an app. This is despite the fact that 29 percent of users have downloaded an app to their phone, and those who do download apps make a frequent practice of it. Fifty-three percent of those who have downloaded apps did so in the last 30 days.

? Games are the most popular apps, according to a partner study with Nielsen, with 60 percent saying they’ve used a game app in the past 30 days. That’s followed by news and weather apps, navigation tools and social networking.

As you’d expect, the study also found that heavy users of apps tend to use all the other advanced features of their phones. Indeed, those who embrace smartphones fully integrate them deeply into their lifestyles.

As the use of smartphones grows, so will the use of apps. For now, app usage on phones remains limited to early adopters, which may have to do with economics as much as anything. With smartphone data plans averaging around $30 a month, on top of voice-plan costs, there’s a large segment of the population not willing to make the leap from a traditional mobile phone to a more capable one.